A transient stability control method and system for microgrids with high proportion of new energy

Abstract

The present invention provides a method and system for transient stability control of microgrids with a high proportion of renewable energy. The method includes a microgrid load monitoring step, a power station response prediction step, a transient stability assessment step, and a distributed power station response step. Transient stability parameters are calculated by comprehensively considering factors such as power station priority and power gap value. The distributed power station response step determines the response capability and selects the responding power station based on these parameters. At the same time, the decentralized coordination control strategy and the distributed power station transmission adjustment step can adjust the power supply rate in real time according to the microgrid voltage value, ensuring that the microgrid voltage is always within a stable range. This dynamic power supply adjustment mechanism enables the microgrid to adapt to various complex operating conditions and improves the operational stability of the microgrid.

Description

Technical Field

[0001] The present invention relates to the field of power grids, and in particular to a method and system for controlling transient stability of a microgrid under a high proportion of renewable energy. Background Art

[0002] With the rapid development and widespread application of new energy technologies, microgrids with high renewable energy penetration have become a crucial component of power systems. As small power systems, microgrids can integrate multiple distributed energy sources, such as photovoltaic power generation, wind power generation, and energy storage systems, enabling local energy production and consumption. However, microgrids with high renewable energy penetrations face numerous challenges in maintaining stable operation. Firstly, renewable energy generation is intermittent and uncertain. For example, photovoltaic power generation is affected by sunlight intensity and weather conditions, while wind power generation is affected by wind speed and direction. These uncontrollable factors lead to significant fluctuations in the output power of renewable energy generation, complicating the stable operation of microgrids. When the output power of renewable energy generation fails to meet the load requirements of the microgrid, it can lead to voltage fluctuations, frequency deviations, and even, in severe cases, microgrid failure. Secondly, microgrids with high renewable energy penetrations often include multiple distributed power stations, each with varying energy source types, geographical locations, and installed capacities, complicating microgrid operation and scheduling. Traditional grid scheduling methods, often designed based on the characteristics and requirements of the larger grid, are ill-suited to the characteristics and requirements of microgrids with high renewable energy penetrations. Furthermore, microgrids operating with a high proportion of renewable energy also need to consider the impact of environmental factors, such as temperature, humidity, and wind speed, on the performance of distributed power plants. Changes in these factors can lead to variations in the efficiency and output power of distributed power plants, thus impacting the stable operation of the microgrid. Therefore, transient stability control methods must comprehensively consider the impact of environmental factors on distributed power plants to improve the operational stability and reliability of the microgrid.

[0003] Therefore, a transient stability control method for microgrids with a high proportion of renewable energy is needed, which can monitor the operating status of the microgrid in real time, intelligently dispatch the power generation of distributed power stations according to the output power of renewable energy power generation and the load demand of the microgrid, and ensure the stable operation of the microgrid. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a microgrid transient stability control method and system for a microgrid with a high proportion of new energy.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for transient stability control of a microgrid with a high proportion of renewable energy includes the following steps:

[0007] a microgrid load monitoring step of obtaining a microgrid power load value, and sending a microgrid transient stability control instruction when the power load value exceeds a preset load threshold;

[0008] a power station response prediction step, receiving a transient stability control instruction, predicting the operating load and power generation of each distributed power station in the microgrid based on the power generation energy type of the distributed power station, and calculating the maximum power supply value of each distributed power station to the microgrid based on the operating load and power generation;

[0009] a transient stability assessment step of selecting a distributed power station that is preferentially used to supply power to the microgrid based on the priority of power stations in the area where the distributed power stations are located, calculating a power gap value of the microgrid after the priority power supply, and calculating a transient stability parameter of each distributed power station based on the microgrid power gap value and the maximum power supply value of each distributed power station using a transient stability assessment strategy;

[0010] The distributed power station response step determines the response capability of the distributed power station supplying power to the microgrid through a decentralized coordinated control strategy according to the transient stability parameters, and selects the distributed power station to respond according to the response capability.

[0011] As a further improvement of the present invention, the power station response prediction step also includes: when the distributed power station is a photovoltaic power station, calculating the operating load of the photovoltaic power station according to the light intensity, temperature and power consumption of the photovoltaic components, and calculating the power generation of the photovoltaic power station according to the light intensity, sunshine time, temperature and conversion efficiency of the photovoltaic components; when the distributed power station is a wind power station, calculating the operating load of the wind power station according to the wind speed, wind direction and power consumption of the wind turbine, and calculating the power generation of the wind power station according to the wind speed, wind direction, air density and operating power of the wind turbine; when the distributed power station is an energy storage power station, calculating the power generation of the energy storage power station according to the battery charging and discharging power and battery charge state of the energy storage power station.

[0012] As a further improvement of the present invention, the power station priority sorting in the transient stability assessment step includes real-time acquisition of the dynamic regulation margin of each distributed power station, the dynamic regulation margin is calculated according to the power station type, when the distributed power station is a photovoltaic power station or a wind power station, the ratio of its current generated power to the maximum adjustable power is calculated, and the dynamic regulation margin is quantified in combination with the virtual inertia support capability of the power station grid-connected inverter; when the distributed power station is an energy storage power station, the dynamic regulation margin is calculated according to the state of charge and the step response rate of the power conversion system, the distributed power stations supplying power to the microgrid are prioritized according to the dynamic regulation margin and the real-time frequency fluctuation rate calculated based on the new energy penetration rate fluctuation index of the area where each distributed power station is located, and the microgrid power gap value at this time is calculated according to the maximum power supply value of the distributed power station with the highest priority and the microgrid power load value.

[0013] As a further improvement of the present invention, it also includes a priority scheduling balancing step. When the maximum power supply value of the distributed power station with the highest priority is greater than the microgrid power load value, the response rate of the distributed power station supplying power to the microgrid is used to judge whether the transient stability requirements are met, and decentralized coordinated control is performed based on the judgment result.

[0014] As a further improvement of the present invention, the transient stability assessment strategy includes: based on the microgrid power gap value and the maximum power supply value of the distributed power station, calculating the microgrid topology structure influence coefficient and the load stability of the distributed power station through the node distance between the microgrid and the distributed power station, and further obtaining the transmission loss of the distributed power station; obtaining the response speed of the distributed power station through the energy reserves of the energy storage power station and the power change speed of the distributed power station; and obtaining the transient stability parameters of each distributed power station based on the environmental factors of the area where the distributed power station is located.

[0015] As a further improvement of the present invention, the transient stability parameter configuration includes:

[0016] ;

[0017] Among them, S i is the transient stability parameter, is the maximum power supply value of the i-th distributed power station, P a is the power gap value of the microgrid, d i is the distance between the i-th distributed power station and the microgrid power receiving station, L i is the load stability amplitude of the i-th distributed power station, which indicates the stability of the distributed power station in maintaining its own power generation. is the electric energy reserve of the i-th distributed power station. When the distributed power station is not an energy storage power station, the value is 0. i is the power change speed of the i-th distributed power station, which indicates the response speed of the distributed power station when supplying power, β i is the comprehensive weight of environmental impact, I N is a normalization function used to unify the value range. ω, μ, u, r, and T are all constants determined based on actual data and are used to adjust the weights and influence of each item in the formula.

[0018] As a further improvement of the present invention, the decentralized coordinated control strategy includes that each distributed power station independently calculates the allowable power supply increment based on the locally detected microgrid voltage value and its own transient stability parameters, and communicates its own allowable power supply increment and current power supply status through the communication system. Each power station performs decentralized power supply coordination based on the received allowable power supply increment of the adjacent power station. At this time, when the allowable power supply increment of the power station is greater than the average allowable power supply increment of the adjacent power stations, the power supply power of the power station is increased; when the allowable power supply increment of the power station is less than the average allowable power supply increment of the adjacent power stations, the distributed power station transmission adjustment step is entered.

[0019] As a further improvement of the present invention, the distributed power station transmission adjustment step includes adjusting the power supply rate of the distributed power station according to the voltage stability evaluation index. When the voltage stability evaluation index is higher than the maximum voltage stability threshold, a gradient voltage reduction control step is executed. At this time, the power supply power is reduced in steps of 10% to 20% of the current power supply rate and continues for a preset control cycle. If the indicator in the next cycle still exceeds the limit, it is switched to a power reduction rate that is inversely proportional to the transient stability parameter of the power station; when the voltage stability evaluation index is lower than the minimum voltage stability threshold, a dual-channel switching control step is executed. At this time, the current power station power supply is immediately stopped, and the standby power station list is activated within 0.5 control cycles. When selecting a power station with a secondary high transient stability parameter, the impedance matching of its power supply line is simultaneously verified, and decentralized coordinated control is performed again.

[0020] A microgrid transient stability control system for a high proportion of renewable energy, comprising:

[0021] A microgrid load monitoring module obtains the power load value of the microgrid and sends a microgrid transient stability control instruction when the power load value exceeds a preset load threshold;

[0022] The power station response prediction module receives the transient stability control instruction, predicts the operating load and power generation of each distributed power station in the microgrid based on the power generation energy type of the distributed power station, and calculates the maximum power supply value of each distributed power station to the microgrid based on the operating load and power generation;

[0023] A transient stability assessment module selects a distributed power station that is preferentially used to supply power to the microgrid based on the priority of the power stations in the area where the distributed power stations are located, calculates the power gap value of the microgrid after the priority power supply, and calculates the transient stability parameters of each distributed power station based on the microgrid power gap value and the maximum power supply value of each distributed power station using a transient stability assessment strategy;

[0024] The distributed power station response module determines the response capability of the distributed power station supplying power to the microgrid through a decentralized coordinated control strategy according to the transient stability parameters, and selects a responding distributed power station according to the response capability.

[0025] The beneficial effects of the present invention are:

[0026] The microgrid load monitoring step of the present invention can obtain microgrid power load values ​​in real time and quickly issue control instructions when the load exceeds a preset threshold. This mechanism ensures that the system can respond promptly to abnormal changes in the microgrid load, laying the foundation for subsequent stable control. Combined with the power station response prediction step, which accurately calculates the operating load and power generation of different types of distributed power stations, the system can make power supply arrangements in advance, effectively avoiding microgrid operational instability caused by sudden load changes.

[0027] The present invention calculates transient stability parameters by comprehensively considering factors such as power plant priority and power shortage value during the transient stability assessment step. The distributed power plant response step determines response capabilities and selects responding power plants based on these parameters. Simultaneously, the decentralized coordinated control strategy and distributed power plant transmission adjustment step adjust the power supply rate in real time based on the microgrid voltage, ensuring that the microgrid voltage remains within a stable range. This dynamic power supply adjustment mechanism enables the microgrid to adapt to various complex operating conditions and improves its operational stability.

[0028] This invention uses a transient stability assessment strategy to calculate transient stability parameters by comprehensively considering multiple factors, including the microgrid topology influence coefficient, the load stability of distributed power stations, transmission losses, response speed, and environmental factors. This comprehensive assessment enables the selection of the optimal power supply combination, minimizing energy losses during transmission. For example, prioritizing power supply from power stations close to the microgrid and with high load stability can effectively reduce power losses on the transmission line. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of a microgrid transient stability control method for a high proportion of new energy in the present invention.

[0030] Figure 2 This is a system block diagram of a microgrid transient stability control system for a high proportion of new energy sources according to the present invention. DETAILED DESCRIPTION

[0031] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments. Identical components are denoted by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, and the terms "bottom," "top," "inner," and "outer" refer to directions toward or away from the geometric center of a particular component, respectively.

[0032] The first embodiment of the present invention proposes a microgrid transient stability control method for a high proportion of new energy. Figure 1 As shown, the following steps are included:

[0033] a microgrid load monitoring step of obtaining a microgrid power load value, and sending a microgrid transient stability control instruction when the power load value exceeds a preset load threshold;

[0034] When a microgrid with a high proportion of renewable energy contains multiple distributed power stations (including wind power stations, hydropower stations, photovoltaic power stations and energy storage stations), power load data is collected in real time in the microgrid. When the power load value is detected to exceed the preset load threshold at a certain moment, the microgrid transient stability control command is immediately sent.

[0035] The power station response prediction step receives a transient stability control command and predicts the operating load and power generation of each distributed power station in the microgrid based on the power generation energy source type of the distributed power stations. Based on the operating load and power generation, the maximum power supply value that each distributed power station can provide to the microgrid is calculated. Distributed power stations can use a variety of power generation energy sources, including solar, wind, and hydropower. Different energy sources have different power generation characteristics. For example, solar power generation is affected by sunlight intensity and duration, while wind power generation is affected by wind speed and direction. Based on the power generation energy source type of the distributed power station, combined with real-time meteorological data such as sunlight intensity and wind speed, as well as the equipment parameters and operating characteristics of the power station, a corresponding prediction model, such as a machine learning-based photovoltaic power generation prediction model or a numerical simulation-based wind power generation prediction model, is used to predict the operating load and power generation of each distributed power station over a period of time. Based on the predicted operating load and power generation, the maximum power supply value that each distributed power station can provide to the microgrid is calculated, taking into account factors such as power station equipment efficiency and line losses, to provide data support for subsequent transient stability assessments.

[0036] The transient stability assessment step includes selecting a distributed power station that is prioritized for supplying power to the microgrid based on the priority of the distributed power stations in their respective regions. The microgrid's power shortfall value after priority power supply is calculated. The transient stability parameters of each distributed power station are calculated using a transient stability assessment strategy based on the microgrid's power shortfall value and the maximum power supply value of each distributed power station. The priority of the distributed power stations in their respective regions is determined based on multiple factors, such as their reliability, power generation costs, and their support for the local power grid. Distributed power stations with higher priorities are preferentially selected to supply power to the microgrid. The power shortfall value of the microgrid after priority power supply is calculated, i.e., the difference between the current microgrid load demand and the power supply of the prioritized distributed power station. Based on the microgrid's power shortfall value and the maximum power supply value of each distributed power station, a transient stability assessment strategy is employed, taking into account the microgrid's electrical parameters, load characteristics, and the control strategy of the distributed power stations, to calculate the transient stability parameters of each distributed power station, such as power adjustment range and voltage stability index.

[0037] The distributed power station response step determines the response capability of the distributed power station supplying power to the microgrid through a decentralized coordinated control strategy based on the transient stability parameters, and selects the distributed power station that responds based on the response capability. Based on the calculated transient stability parameters, a decentralized coordinated control strategy is used to coordinate the operation of each distributed power station. This strategy takes into account the operating status, response capability, and overall stability requirements of each power station to determine the response capability of the distributed power station supplying power to the microgrid. Based on the response capability, a responsive distributed power station is selected to adjust its generated power to supply power to the microgrid to make up for the power gap of the microgrid and maintain the transient stable operation of the microgrid. During the response process, the operating status of the distributed power station and the electrical parameters of the microgrid are monitored in real time, and the control strategy is dynamically adjusted according to the actual situation to ensure the stable operation of the microgrid.

[0038] Specifically, the power station response prediction step further includes, when the distributed power station is a photovoltaic power station, calculating the operating load of the photovoltaic power station based on light intensity, temperature, and photovoltaic module power consumption, and calculating the power generation of the photovoltaic power station based on light intensity, sunshine duration, temperature, and photovoltaic module conversion efficiency. Light intensity directly affects the power generation capacity of photovoltaic modules and is a key input for photovoltaic power generation. Under standard testing conditions, the power generation efficiency of photovoltaic modules is relatively stable, but in real-world environments, temperature has a significant impact on it. When the temperature rises, the open-circuit voltage of the photovoltaic modules decreases, resulting in a decrease in power generation efficiency. Using a professional temperature sensor to monitor the operating temperature of the photovoltaic modules in real time, combined with the module characteristic curve, an accurate temperature correction coefficient can be derived. When the distributed power station is a wind power station, calculating the operating load of the wind power station based on wind speed, wind direction, and wind turbine power consumption, and calculating the power generation of the wind power station based on wind speed, wind direction, air density, and wind turbine operating power. Wind speed is a key factor influencing wind power generation: the higher the wind speed, the more wind energy the wind turbine captures, resulting in higher power generation. Wind direction determines the angle of contact between wind turbine blades and the wind, significantly impacting the turbine's operating efficiency and stress. Real-time wind speed and direction data is obtained through anemometers and wind vanes installed at wind farms. During operation, wind turbines consume a certain amount of energy, known as wind turbine power consumption, due to their own equipment. This is determined by factors such as the turbine model and operating status. When calculating the operating load of a wind power station, it can be expressed as: operating load = wind speed × wind direction correction factor × wind turbine power consumption. The wind direction correction factor reflects the impact of different wind directions on wind turbine power consumption. Air density is also a key parameter when calculating power generation, as it is related to factors such as local altitude, temperature, and air pressure. Wind turbine operating power reflects the turbine's power generation capacity at different wind speeds and is typically determined by the turbine's power curve. When the distributed power station is an energy storage station, the power generation of the energy storage station is calculated based on the battery charge and discharge power and battery state of charge.

[0039] Specifically, the power station priority ranking in the transient stability assessment step includes real-time acquisition of the dynamic regulation margin of each distributed power station, the dynamic regulation margin is calculated according to the type of power station, when the distributed power station is a photovoltaic power station or a wind power station, the ratio of its current generated power to the maximum adjustable power is calculated, and the dynamic regulation margin is quantified in combination with the virtual inertia support capability of the power station grid-connected inverter; when the distributed power station is an energy storage power station, the dynamic regulation margin is calculated according to the state of charge and the step response rate of the power conversion system, the distributed power stations supplying power to the microgrid are prioritized according to the dynamic regulation margin and the real-time frequency fluctuation rate calculated based on the new energy penetration rate fluctuation index of the area where each distributed power station is located, and the microgrid power gap value at this time is calculated according to the maximum power supply value of the distributed power station with the highest priority and the microgrid power load value.

[0040] Specifically, the system also includes a priority scheduling balancing step. When the maximum power supply value of the highest-priority distributed power station exceeds the microgrid's power load, the distributed power station's response rate to the microgrid is used to determine whether it meets transient stability requirements. Decentralized coordinated control is then implemented based on the determination result. To calculate the response rate, the response rate of the highest-priority power station must be accurately measured or estimated—that is, the time it takes from receiving a power supply command to actually starting power supply. This response rate is then compared with a preset transient stability requirement threshold. If the response rate is less than or equal to the threshold, the power station is deemed to meet the transient stability requirements; otherwise, it fails to meet them. Based on the response rate determination, the system implements a corresponding control strategy. If the power station meets the transient stability requirements, it can continue to supply power to the microgrid, and its power supply status and microgrid operation are monitored in real time. If the power station does not meet the transient stability requirements, a decentralized coordinated control strategy is activated. This means that the system comprehensively considers factors such as the power supply capabilities and response rates of other distributed power stations, as well as the actual needs of the microgrid, and uses intelligent algorithms or optimization models to reallocate power supply tasks to ensure the overall stability of the microgrid.

[0041] Specifically, the transient stability assessment strategy includes calculating the microgrid topology influence coefficient, the load stability of the distributed power station, and further calculating the transmission loss of the distributed power station based on the microgrid power gap value and the maximum power supply value of the distributed power station through the node distance between the microgrid and the distributed power station; calculating the response speed of the distributed power station based on the energy storage capacity of the energy storage station and the power change speed of the distributed power station; and comprehensively calculating the transient stability parameters of each distributed power station based on the environmental factors in the area where the distributed power station is located. The transient stability parameter configuration includes:

[0042] ;

[0043] Among them, S i is the transient stability parameter, is the maximum power supply value of the i-th distributed power station, P a is the power gap value of the microgrid, d i is the distance between the i-th distributed power station and the microgrid power receiving station, L i is the load stability amplitude of the i-th distributed power station, which indicates the stability of the distributed power station in maintaining its own power generation. is the electric energy reserve of the i-th distributed power station. When the distributed power station is not an energy storage power station, the value is 0. i is the power change speed of the i-th distributed power station, which indicates the response speed of the distributed power station when supplying power, β i is the comprehensive weight of environmental impact, I N is a normalization function used to unify the value range. ω, μ, u, r, and T are all constants determined based on actual data and are used to adjust the weights and influence of each item in the formula.

[0044] Specifically, the decentralized coordinated control strategy includes selecting the distributed power station with the highest transient stability parameter to supply power to the microgrid, detecting the microgrid voltage value in real time during the power supply process, and constructing a voltage stability evaluation index based on the microgrid voltage value. When the voltage stability evaluation index does not fall within the preset voltage stability threshold range, the distributed power station transmission adjustment step is entered.

[0045] Specifically, the distributed power station transmission adjustment step includes adjusting the distributed power station's power supply rate based on the voltage stability assessment index. When the voltage stability assessment index exceeds the maximum voltage stability threshold, the distributed power station's power supply rate is reduced. When the voltage stability assessment index falls below the minimum voltage stability threshold, the distributed power station is stopped from supplying power, and a distributed power station with the next highest transient stability parameter is selected to supply power to the microgrid, and decentralized coordinated control is resumed. During the power supply process, the system continuously monitors the microgrid's voltage value in real time. This step is crucial to ensuring the stable operation of the microgrid, as voltage fluctuations can directly impact the safety and efficiency of grid equipment. Based on the real-time monitored microgrid voltage value, the system constructs a voltage stability assessment index. This index comprehensively reflects the current voltage stability of the microgrid and provides a basis for subsequent control decisions. If the voltage stability assessment index falls outside the preset voltage stability threshold range, it indicates that the microgrid's voltage stability is threatened. In this case, the system must immediately take appropriate measures to adjust the distributed power station's transmission to ensure that the microgrid's voltage returns to a stable state. After entering the distributed power station transmission adjustment step, the system will formulate a reasonable transmission adjustment plan based on the specific values ​​of the voltage stability assessment indicators, as well as factors such as the current microgrid load situation and the power supply capacity of the distributed power station to ensure the transient stability of the power grid.

[0046] A microgrid transient stability control system for high proportion of renewable energy, such as Figure 2 Shown, including:

[0047] A microgrid load monitoring module obtains the power load value of the microgrid and sends a microgrid transient stability control instruction when the power load value exceeds a preset load threshold;

[0048] The power station response prediction module receives the transient stability control instruction, predicts the operating load and power generation of each distributed power station in the microgrid based on the power generation energy type of the distributed power station, and calculates the maximum power supply value of each distributed power station to the microgrid based on the operating load and power generation;

[0049] A transient stability assessment module selects a distributed power station that is preferentially used to supply power to the microgrid based on the priority of the power stations in the area where the distributed power stations are located, calculates the power gap value of the microgrid after the priority power supply, and calculates the transient stability parameters of each distributed power station based on the microgrid power gap value and the maximum power supply value of each distributed power station using a transient stability assessment strategy;

[0050] The distributed power station response module determines the response capability of the distributed power station supplying power to the microgrid through a decentralized coordinated control strategy according to the transient stability parameters, and selects a responding distributed power station according to the response capability.

[0051] The above shows and describes the basic features, principles, and advantages of the present invention. It should be noted that the present invention is not limited to the above embodiments, which are only some embodiments. Without departing from the spirit and scope of the present invention, various improvements and supplements made are considered to be within the scope of protection of the present invention.

Claims

1. A microgrid transient stability control method for a high proportion of new energy, characterized by: The steps include: a microgrid load monitoring step of obtaining a microgrid power load value, and sending a microgrid transient stability control instruction when the power load value exceeds a preset load threshold; a power station response prediction step, receiving a transient stability control instruction, predicting the operating load and power generation of each distributed power station in the microgrid based on the power generation energy type of the distributed power station, and calculating the maximum power supply value of each distributed power station to the microgrid based on the operating load and power generation; a transient stability assessment step of selecting a distributed power station that is preferentially used to supply power to the microgrid based on the priority of power stations in the area where the distributed power stations are located, calculating a power gap value of the microgrid after the priority power supply, and calculating a transient stability parameter of each distributed power station based on the microgrid power gap value and the maximum power supply value of each distributed power station using a transient stability assessment strategy; a distributed power station response step, determining the response capability of the distributed power stations supplying power to the microgrid through a decentralized coordinated control strategy according to the transient stability parameters, and selecting a responding distributed power station according to the response capability; The transient stability parameter configurations are: ； Among them, S i is the transient stability parameter, is the maximum power supply value of the i-th distributed power station, P a is the power gap value of the microgrid, d i is the distance between the i-th distributed power station and the microgrid power receiving station, L i is the load stability amplitude of the i-th distributed power station, which indicates the stability of the distributed power station in maintaining its own power generation. is the electric energy reserve of the i-th distributed power station. When the distributed power station is not an energy storage power station, the value is 0. i is the power change speed of the i-th distributed power station, which indicates the response speed of the distributed power station when supplying power, β i is the comprehensive weight of environmental impact, I N is a normalization function used to unify the value range. ω, μ, u, r, and T are all constants determined based on actual data and are used to adjust the weights and influence of each item in the formula.

2. The microgrid transient stability control method for a high proportion of new energy according to claim 1 is characterized in that: The power station response prediction step also includes, when the distributed power station is a photovoltaic power station, calculating the operating load of the photovoltaic power station according to the light intensity, temperature and power consumption of the photovoltaic components, and calculating the power generation of the photovoltaic power station according to the light intensity, sunshine time, temperature and conversion efficiency of the photovoltaic components; when the distributed power station is a wind power station, calculating the operating load of the wind power station according to the wind speed, wind direction and power consumption of the wind turbine, and calculating the power generation of the wind power station according to the wind speed, wind direction, air density and operating power of the wind turbine; when the distributed power station is an energy storage power station, calculating the power generation of the energy storage power station according to the battery charging and discharging power and battery charge state of the energy storage power station.

3. The microgrid transient stability control method for a high proportion of new energy according to claim 1, characterized in that: The power station priority sorting in the transient stability assessment step includes real-time acquisition of the dynamic regulation margin of each distributed power station, the dynamic regulation margin is calculated according to the power station type, when the distributed power station is a photovoltaic power station or a wind power station, the ratio of its current generated power to the maximum adjustable power is calculated, and the dynamic regulation margin is quantified in combination with the virtual inertia support capability of the power station grid-connected inverter; when the distributed power station is an energy storage power station, the dynamic regulation margin is calculated according to the state of charge and the step response rate of the power conversion system, the distributed power stations supplying power to the microgrid are prioritized according to the dynamic regulation margin and the real-time frequency fluctuation rate calculated based on the new energy penetration rate fluctuation index of the area where each distributed power station is located, and the microgrid power gap value at this time is calculated according to the maximum power supply value of the distributed power station with the highest priority and the microgrid power load value.

4. The microgrid transient stability control method for a high proportion of new energy according to claim 1, characterized in that: It also includes a priority scheduling balancing step. When the maximum power supply value of the distributed power station with the highest priority is greater than the microgrid power load value, the response rate of the distributed power station supplying power to the microgrid is used to judge whether the transient stability requirements are met, and decentralized coordinated control is performed based on the judgment result.

5. The microgrid transient stability control method for a high proportion of new energy according to claim 1, characterized in that: The transient stability assessment strategy includes calculating the microgrid topology influence coefficient, the load stability of the distributed power station, and further calculating the transmission loss of the distributed power station based on the microgrid power gap value and the maximum power supply value of the distributed power station through the node distance between the microgrid and the distributed power station; calculating the response speed of the distributed power station based on the energy reserves of the energy storage power station and the power change speed of the distributed power station; and comprehensively calculating the transient stability parameters of each distributed power station based on environmental factors in the area where the distributed power station is located.

6. The microgrid transient stability control method for a high proportion of new energy according to claim 1, characterized in that: The decentralized coordination control strategy includes: each distributed power station independently calculates the allowable power supply increment based on the locally detected microgrid voltage value and its own transient stability parameters, and communicates its own allowable power supply increment and current power supply status to the power station through the communication system. Each power station performs decentralized power supply coordination based on the allowable power supply increment received from adjacent power stations. At this time, when the allowable power supply increment of the power station is greater than the average allowable power supply increment of the adjacent power stations, the power supply of the power station is increased; When the allowable power supply increment of the power station is less than the average allowable power supply increment of the adjacent power stations, the distributed power station transmission adjustment step is entered.

7. The microgrid transient stability control method for a high proportion of new energy according to claim 1, characterized in that: The distributed power station transmission adjustment step includes adjusting the power supply rate of the distributed power station according to the voltage stability evaluation index. When the voltage stability evaluation index is higher than the maximum voltage stability threshold, a gradient voltage reduction control step is executed. At this time, the power supply is reduced in steps of 10% to 20% of the current power supply rate and continues for a preset control cycle. If the indicator in the next cycle still exceeds the limit, it is switched to a power reduction rate that is inversely proportional to the transient stability parameter of the power station; when the voltage stability evaluation index is lower than the minimum voltage stability threshold, a dual-channel switching control step is executed. At this time, the current power station is immediately stopped from supplying power, and a list of standby power stations is activated within 0.5 control cycles. When a power station with a secondary higher transient stability parameter is selected, the impedance matching of its power supply line is simultaneously verified, and decentralized coordinated control is performed again.

8. A microgrid transient stability control system for a high proportion of renewable energy, applicable to a microgrid transient stability control method for a high proportion of renewable energy according to any one of claims 1 to 7, characterized in that: include: A microgrid load monitoring module obtains the power load value of the microgrid and sends a microgrid transient stability control instruction when the power load value exceeds a preset load threshold; The power station response prediction module receives the transient stability control instruction, predicts the operating load and power generation of each distributed power station in the microgrid based on the power generation energy type of the distributed power station, and calculates the maximum power supply value of each distributed power station to the microgrid based on the operating load and power generation; A transient stability assessment module selects a distributed power station that is preferentially used to supply power to the microgrid based on the priority of the power stations in the area where the distributed power stations are located, calculates the power gap value of the microgrid after the priority power supply, and calculates the transient stability parameters of each distributed power station based on the microgrid power gap value and the maximum power supply value of each distributed power station using a transient stability assessment strategy; The distributed power station response module determines the response capability of the distributed power station supplying power to the microgrid through a decentralized coordinated control strategy according to the transient stability parameters, and selects a responding distributed power station according to the response capability.

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